1. Field of the Invention
This application is directed to thioester derived hindered phenols and thioester derived arylamines as antioxidant and antiwear additives for lubricants and fuels and to compositions containing same.
2. Description of Related Art
Arylamines and hindered phenols have been traditionally and extensively used as oxidation inhibitors and sulfur-containing compounds as antiwear compounds for lubricants. We have found that specific combinations of arylamines or hindered phenols with sulfur-containing compounds can result in a synergistic mixture and give a much enhanced antioxidative stabilization for lubricants. Disclosed in this patent application are examples of effective combinations of arylamines or hindered phenols with sulfur-containing compounds for lubricant compositions. These same compositions also provide remarkable EP/antiwear activity. Improvements in anti-fatigue, antirust, cleanliness, antifatigue, extreme pressure, antistaining, detergent, anti-corrosion and demulsibility properties are also expected. These unique additives can also be used in hydrocarbon, oxygenated or mixed fuels for any of the above purposes.
This invention more particularly provides highly effective multifunctional antioxidant and antiwear additives for lubricant and fuel compositions comprising thioester derived arylamines and hindered phenols and fuel and lubricant compositions comprised thereof. The invention accordingly provides these additives in a new class of novel compositions.
This case of antioxidants consist of the reaction products of arylamines (such as Vanderbilt's Vanlube 81) or hindered phenols (such as Ethyl Corp.'s Ethanox 754 with hydrocarbyl e.g., alkenyl or polyalkenyl, e.g., polyisobutenyl anhydrides and thioesters (such as glycol dimercaptoacetate). We have found that these additives are very effective antioxidant and antiwear compositions for lubricant applications. To the best of ourknowledge, the syntheses, uses, and applications of this family of antioxidants to lubricant and fuel compositions have not been reported elsewhere or used commercially, and are therefore novel.
An object of this invention is to provide improved lubricant and fuel compositions having increased multifunctional antioxidant and antiwear characteristics. It is, also, an object of this invention to provide novel multifunctional lubricant and fuel additives and novel uses of the described additives in such compositions.